diff --git a/hw/m48t59.c b/hw/m48t59.c
index 6991e2e8e1..2020487bbe 100644
--- a/hw/m48t59.c
+++ b/hw/m48t59.c
@@ -642,6 +642,7 @@ M48t59State *m48t59_init(qemu_irq IRQ, target_phys_addr_t mem_base,
     DeviceState *dev;
     SysBusDevice *s;
     M48t59SysBusState *d;
+    M48t59State *state;
 
     dev = qdev_create(NULL, "m48t59");
     qdev_prop_set_uint32(dev, "type", type);
@@ -649,18 +650,18 @@ M48t59State *m48t59_init(qemu_irq IRQ, target_phys_addr_t mem_base,
     qdev_prop_set_uint32(dev, "io_base", io_base);
     qdev_init_nofail(dev);
     s = sysbus_from_qdev(dev);
+    d = FROM_SYSBUS(M48t59SysBusState, s);
+    state = &d->state;
     sysbus_connect_irq(s, 0, IRQ);
     if (io_base != 0) {
-        register_ioport_read(io_base, 0x04, 1, NVRAM_readb, s);
-        register_ioport_write(io_base, 0x04, 1, NVRAM_writeb, s);
+        register_ioport_read(io_base, 0x04, 1, NVRAM_readb, state);
+        register_ioport_write(io_base, 0x04, 1, NVRAM_writeb, state);
     }
     if (mem_base != 0) {
         sysbus_mmio_map(s, 0, mem_base);
     }
 
-    d = FROM_SYSBUS(M48t59SysBusState, s);
-
-    return &d->state;
+    return state;
 }
 
 M48t59State *m48t59_init_isa(uint32_t io_base, uint16_t size, int type)